Background: Autonomic nervous system (ANS) dysfunction has been correlated with fasting insulin and glucose, independent of clinically diagnosed diabetes. We tested whether men and women (aged 45 to 64 years) from the Atherosclerosis Risk In Communities study (n=8185) with ANS dysfunction, estimated by high heart rate (HR) and low HR variability (HRV), were at increased risk for developing type 2 diabetes.
Methods and results: Supine HR and HRV indices were measured for 2 minutes at baseline; indices were divided into quartiles for analyses. From 1987 to 1998 (mean follow-up 8.3 years), there were 1063 cases of incident diabetes. The relative risk (RR) of developing diabetes for participants with low-frequency (LF) power (0.04 to 0.15 Hz) HRV in the lowest quartile (<7.7 ms2) compared with the highest quartile (> or =38.9 ms2) was 1.2 (95% CI 1.0-1.4) after adjustment for age, race, sex, study center, education, alcohol drinking, current smoking, prevalent coronary heart disease, physical activity, and body mass index. Participants in the uppermost (>72.7 bpm) versus the lowest (< or =60.1 bpm) quartile of HR had a 60% increased risk (95% CI 33%-92%) of developing diabetes. Results were similar when the sample was restricted to participants with normal fasting glucose (glucose <6.1 mmol/L) at baseline (n=7192) or when adjusted for baseline glucose (HR quartile 4 versus quartile 1, RR=1.4, 95% CI 1.2-1.7).
Conclusions: These findings suggest that ANS dysfunction may be associated with the development of diabetes in healthy adults.